BUG: unable to handle kernel paging request in trace_hardirqs_on_thunk

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: c6db52a8 Linux 4.14.183
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=154229b1100000
kernel config: https://syzkaller.appspot.com/x/.config?x=98bbe4d18401ff4
dashboard link: https://syzkaller.appspot.com/bug?extid=bc4b8c192add232003b4
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+bc4b8c...@syzkaller.appspotmail.com

squashfs: SQUASHFS error: Can't find a SQUASHFS superblock on nullb0
squashfs: SQUASHFS error: Can't find a SQUASHFS superblock on nullb0
BUG: unable to handle kernel paging request at ffffffffd5e8087d
IP: trace_hardirqs_on_thunk+0x11/0x1c
PGD 7a6d067 P4D 7a6d067 PUD 7a6f067 PMD 0
Oops: 0002 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 6349 Comm: syz-executor.2 Not tainted 4.14.183-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880609ec180 task.stack: ffff8880609f0000
RIP: 0010:trace_hardirqs_on_thunk+0x11/0x1c
RSP: 0018:ffff8880609f7f08 EFLAGS: 00010082
RAX: ffff8880609ec180 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880609ec188
RBP: ffff8880609f7f48 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000002b63940(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffd5e8087d CR3: 00000000608eb000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
entry_SYSCALL_64_after_hwframe+0x56/0xbb
RIP: 0033:0x45af70
RSP: 002b:00007ffe0fe549a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000023
RAX: 0000000000000000 RBX: 000000000004abc5 RCX: 000000000045af70
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007ffe0fe549b0
RBP: 00000000000006c5 R08: 0000000000000001 R09: 0000000002b63940
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000a
R13: 00007ffe0fe54a00 R14: 000000000004a85d R15: 00007ffe0fe54a10
Code: 00 48 c7 84 dc 40 01 00 00 00 00 00 00 8b 44 24 5c 89 44 24 58 e9 5b fd ff ff 55 48 89 e5 57 56 52 51 50 41 50 41 51 41 52 00 00 <00> 8b 7d 08 e8 d5 05 46 00 eb 64 55 48 89 e5 57 56 52 51 50 41
RIP: trace_hardirqs_on_thunk+0x11/0x1c RSP: ffff8880609f7f08
CR2: ffffffffd5e8087d
---[ end trace 39d107e37e833141 ]---


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.